Lubricating compositions



United States Patent LUBRICATING COlVIPOSITIONS John L. Van Winkle, SanLorenzo, Edward R. Bell, Concord, and Rupert C. Morris, Berkeley,Calif., assignors to Shell Development Company, New York, N. Y., acorporation of Delaware No Drawing. Application May 19, 1955, Serial No.509,682

11 Claims. Cl. 252-325 This invention relates to lubricants particularlysuitable for use in equipment operating under extreme pressure, highspeeds and wide temperature range conditions.

It is known that certain classes of compounds can improve various typesof bases such as lubricating oils or fuel oils in certain specificproperties. Thus, soaps or organic salts generally are regarded as beingcapable of imparting detergency to base lubricants, whereas compoundscontaining chlorine, sulfur, phosphorus or lead are capable of impartingextreme pressure characteristics to lubricants. The combination ofadditives wherein each additive exerts its influence without interferingwith the function of other additives is rather diflicult to attain. Inmost cases, interference or co-reaction occurs negating the desirableproperties of the additives involved.

It is an object of this invention to improve lubricants by additionthereto of a novel multifunctional additive. Another object of thisinvention is to produce improved lubricants of outstanding stability andextreme pressure properties. Another object of this invention is toprevent oxidation of lubricants and corrosion and wear of surfacescontacted by said lubricants. Other objects of this invention will beapparent from the following description of this invention.

It has now been discovered that the foregoing and related ends can beaccomplished by addition to a lubricant a minor amount of an organicphosphorus compound having the general formula:

wherein X is a chalcogen element and preferably is either oxygen orsulfur, R is a hydrocarbyl radical containing at least one andpreferably more than one halogen atom not more than four carbon atomsremoved from the phosphorus atom, said radical R being directly linkedto the phosphorus atom through a carbon atom, of which preferred'is whenR is a C(Hal)3 radical wherein Hal stands for a halogen, e. g., chlorineor bromine; R and R can be hydrogen or the same or different hydrocarbylradicals, preferably alkyl radicals; and Y can be (2) XH radical; (3) XRradical or (4)XZ wherein R R and X are the same as defined above, R is ahydrocarbyl radical, e. g., alkyl, cycloalkyl or aralkyl radical and Zis a salt forming cation such as an amine, preferably an aliphaticamine.

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The monoamido phosphono ester, which can be used as additives incompositions of this invention can be prepared by the methods describedin our co-pending application, Serial No. 369,232, filed July 20, 1953,now U. S. Patent 2,712,029, of which the present application is acontinuation-in-part. The acids or salts of the esters as described inthe parent case can be prepared by any suitable means such as bypyrolysis of the ester to form the amido acid and if desired the acidcan be converted to a salt by neutralizing the acid with an amine or ametal compound such as calcium hydroxide. The diamido or the otherderivatives of the phosphono compounds of this invention can be preparedby reacting organo phosphorus dihalides (which have been described byKinnear and Perren in the Journal of the Chemical Society, 1952, pages3437 to 3445) with an amine. Prior to converting organo phosphorusdihalides of the type described by Kinnear and Perren to an amidoderivative, one of the halides can be replaced by an ester, acid orother polar group or by a hydrocarbyl radical. If the Kinnear and Perrenintermediate dihalide compounds are used as a starting material, thereaction can be generally carried out at low temperatures of from about-10 to about 20 C., and preferably at zero to 5 C., preferably in thepresence of an HCl acceptor and an inert solvent such as benzene and thelike.

Starting trivalent phosphorus compounds for the preparation ofamido-phosphono additives of this invention include mono and di-estersof amido phosphites and thiophosphites such as mono and dialkyl, aryl orcycloalkyl esters of amido phosphite, which can be illustrated mono ordialkyl (C1 to C18) amidophosphites, e. g., mono and diisopropyl, monoand dibutyl, mono and di-Z-ethylhexyl and mono and dioctadecylphosphites, mono or dicycloalkyl amido phosphites, e. g., mono ordicyclohexyl amido phosphite, 2-N,N-bis(2-ethylhexyl)amino-1,3,2-dioxaphospholane; acids or esters of amido halophosphitessuch as N-butylamido chloro acid phosphite, butyl N-Z-ethylhexyl amidochlorophosphite; amido dihalophosphites such as N,N-butylamidodichlorophosphite. Other starting phosphorus compounds include thosedescribed by Kinnear and Perren as well as various derivatives.

Suitable amines which can be employed in the preparation of the amidesof the present invention include aliphatic amines, alicyclic amines,aromatic amines, heterocyclic amines and mixtures thereof having a totalof not more than about 40 carbon atoms of which the mono anddialkylamines in which each alkyl group contains from 1 to 20 carbonatoms are preferred. Examples of such amines include primary orsecondary saturated and unsaturated aliphatic amines, such as methylallyl, propyl, butyl, 2-ethylhexyl, cetyl, dodecyl, oleyl andoctadecylamines; alicyclic amines, such as cyclohexyl, methylcyclohexyl,cyclopentylamines and homologs and analogs thereof; aromatic amines,such as, aniline and naphthylamine; heterocyclic amines such aspiperidine, morpholine and the like. 7

The following examples serve to illustrate the novel amides of thepresent invention and their preparation. It will be appreciated that thefollowing examples are presented with the intent to illustrate ratherthan to limit the invention as it is defined in the hereto appendedclaims.

Example I.-n Butyl N,N DiisopropylamidotrichlaromethanephosphonateDibutyl diisopropylamido phosphite was prepared by reacting diisopropylamine with phosphorus trichloride, thereby obtainingdiisopropylamidodichlorophosphite which was then reacted with sodiumn-butoxide. resulting di-n-butyl N,N-diisopropylamidophosphite was addedslowly, over a period of about one hour and with stirring, to excesscarbon tetrachloride. The temperature of the reaction mixture was C.Stirring was continued at 0 C. for about 1 hour, after which the mixturewas allowed to warm overnight. The warmed mixture was refluxed for 12hours and then stirpped to 130 C., kettle temperature through amolecular still operating with the thimble at 76 C. The distillate had arefractive index, 121 of 1.4730. Analysis: Found, 7.3% hydrogen, 4.3%nitrogen, 10.6% phosphorous; calculated, 6.8% hydrogen, 4.13% nitrogen,9.15% phosphor-us, all percentages being by weight.

Example II.N butylamidotrichloromethaizcplzosplzonic acid ExampleHI.Di-Z-ethylhexylamine salt of N-butyl aamidolrichlorometlzanephosphonic acid To the acid of Example Ii wasadded di-Z-ethylhexylamine in an amount sufiicient to neutralize theacid and the mixture was agitated at around 50 C. The salt formed wasoil-soluble and had good extreme pressure properties. 1

Example lV.N,N'-di-n butyl trichloromethanephosphonic diamide About onemole of trichloromethanephosphonic dichloride was reacted with about twomoles of n-butyl amine in the presence of triethylamine in a benzenesolution and at around O5 C. The final product was recovered by themethod described in Example 11.

Example V.Phenyl N-lmzylamidotrichloromezhanephosphomife About one moleof trichloromethanephosphonic dichloride was reacted with one mole ofphenol in a henzene solution containing triethylamine as an HCl acceptorat around 05 C. The benzene solution was filtered, the benzene wasflashed off and the product recovered wasphenyltrichloromethanechlorophosphonate. The phenyl ester was reactedwith a stoichiometric amount of n-butylamine under the above describedconditions and recovered after filtering and removing the benzene wasphenyl N-butylamidotrichloromethanephosphonate. Analysis of the productwas: Found, 38.3% carbon, 4.6% hydrogen, 9.4% phosphorus, 31.8% chlorineand 4.05% nitrogen; calculated, 39.9% carbon, 4.54% hydrogen, 9.38%phosphorus, 32.2% chlorine and 4.23% nitrogen, melting point 85 C. andit boiled at 114 at 0.003 mm. pressure.

Example VI.n-Butylamidotrichloromethanephosplzolmte This compound wasprepared in the same manner as the additive of Example V except thatn-butanol was used in the place of phenol.

Other representative examples of novel amides of the present inventioninclude the following: N-methylamidotri'chloromethanephosphonic acid,N-isopropylamidotrichloromethanephosphonic acid,N,N-dimethylamidotrichloromethanephosphonic acid,N,N-diisopropylamidotrichloromethanephosphonic acid,N,N-bis(2-ethylhexyl)- amidotrichloromethanephosphonic acid,N,N-dicyclo- The hexylamidotrichloromethanephosphonic acid; the methyl,ethyl, butyl, cyclohexyl, 2-ethylhexyl, benzyl and vinyl esters of saidacids and the ammonium, C12C15 alkylamine, such as a Primenemanufacturedby Rohm and Haas, di-2-ethylhexylamine and octadecylamine salts of saidacids and the corresponding tribromo and triiodo amido phosphoruscompounds.

The phosphorus compounds of this invention are generally used in amountsvarying from about 0.01% to about 10% and preferably between about 0.1%and 5% by weight, depending upon the medium they are used in and use towhich they are put.

In cases where the phosphorus compounds are not sufficiently soluble inthe medium to which they are added, such as fuel oils, lubricating oilsand the like, they can be eifectively dispersed or solubilized by meansof alcohols, preferably branched chain alkanols. Alcohols of this typecan be obtained by the 0x0 process described in the Oil and Gas Journal,June 9, 1949, and in the February 1953 issue of Petroleum Processing.Other types of alcohols such as the straight or branched chain fattyalcohols can be used as Well their thiol analogues. Examples of suitablealcohols are: hexyl, heptyl, octyl, nonyl, decyl, dodecyl, tridecyl,tetradecyl, octadecyl, benzyl, cyclohexyl, dimethyl cyclohexyl,3,3,5-trimethylcyclohexyl, oleyl alcohols, sperm oil alcohol, woolgrease alcohol, Oxo CsC1s alcohols (produced from olefins, carbonmonoxide and hydrogen by the Oxo'reaction), petroleum alcohols, du Pontalcohols of the B21 to B series,'Archer-Daniels-Midland Adols, which arehigher fatty alcohols. The thiol analogues of these alcohols such asdescribed in U. S. Patent 2,638,448 and including isooctanethiol,decanethoil, octadecanethiol, tertiary tetradecanethiol, tertiaryhexadecanethiol and the like or mixtures of said alcohols and/or thiolscan be used with the phosphorus compounds in accordance with thisinvention.

The solubilizers of this invention can be used in amounts of from 0.5 to10% and preferably from 1 to 5%, depending upon the type of phosphorusadditive and base oil used in forming compositions of the invention.Generally, a relatively oil-insoluble phosphorus additive of thisinvention can be solubilized and stabilized from long periods of timesuch as in excess of 3 to 12 months under wide temperature conditions byuse of the order of 3%, based on the total composition, of an alkanoland/ or alkanthiol as described.

Base oils to which agents of this invention are added may be selectedfrom a variety of natural oils such as parafi'inic, naphthenic, andmixed base mineral oils having a viscosity range such as from at 100 F.,SUS, to up to 250 SUS at 210 F. In addition, synthetic oils may be usedsuch as polymerized olefins, alkylated aromatics; polyalkyl siliconepolymers, e. g., liquid dimethyl silicone polymer and other siliconepolymers; HzS-adducts of unsaturated ethers and thioethers, e. g.,

. H28 adduct of diallyl ether; esters, e. g., di(2-ethylhexyl) and usedas the base oil. Also, the base can be gasoline,

fuel oil, hydraulic fluids, and the like.

Compositions of this invention were evaluated as extreme pressure agentsby use of the Four-Ball Extreme Pressure Lubricating Tester similar inprinciple to the Boerlage apparatus described in the magazine,Engineering, volume 136, July 13, 1933. This apparatus comprises foursteel balls arranged in a pyramid formation. The top ball is rotated byspindles against the three bottom balls which are clamped in astationary ball holder. The balls'are immersed in the composition to betested. Tests were run under conditions indicated in the following TableI and compared with other outstanding extreme pressure compounds.

5 TABLE I Four-ball evaluation of EP compositions [1620 R. P. M.; 1minute, steel on steel, ambient temperature] Amount, Initial Base OilAdditive percentwt. Seizure Load, Kg.

1. SHAE 90, mineral 40-45 2. SAE 90, mineral Pass-Chlorinated sperm oil10% 79 oil. reaction product contain g 7% S, 0.2% P and 0.3% CI. 3.Bpick Hypoid 56-71 01 Pb oleate 67 131cc gs'mmeml Chlorinated parafifinwax 3%: f 71 o Suliurized fish oil 20-25% 5. SAE 90, mineral {Examplel0.4% 01 oil. Tridecyl aleohoL 1. G. SAE 90, mineral {Example 0 4% Cl126441 s in 90 1 rifirldeesil iri 0 4; iii

7. minera ramp 9 s "s in 90 1 i i i r 01- 0 4 (ii 126441 minera xamp e 00' Trideeyl alcohol- 1.5% i 112 126 9. SAE 90, mineral Example 0.4% 01100-112 10. EA 90, mineral Example V 0.4% 01 100-112 11. flSAE 10,mineral Examplel 0.42% 01 130-140 12. SAE 10, mineral N ,N-bis(Z-ethylhexyl) 0.2% Cl 150-160 oil. amido trichloromethaanephosphonicacid.

Results similar to those obtained with Compositions 5 to 12 in theFour-Ball EP Tester can be attained by substituting the amido-phosphonoadditives in said compositions with the amido-phosphono additives listedon columns 6 and 7 of the specification in concentrations of from 0.2%to 0.8% based on the halogen content of the additive.

Compositions of this invention can be combined with other additives inlubricants, such as anti-oxidants, corrosion inhibitors, wear reducer,blooming agents, pour point depressants or viscosity improvers,anti-foaming agents, e. g., dimethyl silicone polymer and the like.

Depending upon the primary additives used and conditions under whichthey are used, the amount of secondary additives used may vary fromabout 0.01% to about 2% or higher.

We claim as our invention:

1. A composition of matter comprising a major amount of a lubricatingoil and a minor amount, sufficient to impart extreme pressure propertiesto said liquid oil, of a compound having the general formula wherein Xis oxygen, R is a chloroalkyl radical linked directly to phosphorusthrough a carbon atom, Y is a polar radical selected from the groupsconsisting of (1) same as wherein R and R are selected from the groupconsisting if hydrogen and hydrocaIbyl radicals selected from the groupconsisting of alkyl and cycloalkyl radicals having from 1 to 20 carbonatoms; (2) -OH, (3) OR wherein R is a hydrocarbyl radical selected fromthe group consisting of alkyl and cycloalkyl radicals and (4) -OZwherein Z is an ammonium radical.

2. A composition of claim 1 wherein X is oxygen and, R is aCCls radical.

3. A composition of claim 1 wherein the lubricating oil is a minerallubricating oil.

4. A composition of matter comprising a major amount of minerallubricating oil and a minor amount, sufiicient to impart extremepressure to said oil, of a diarnide of a trichloromethane phosphonicacid derived from an amine having a total of not more than about carbonatoms.

5. A composition of matter comprising a major amount of minerallubricating oil and a minor amount, sufiicient to impart extremepressure to said oil of an alkyl amide of trichloromethane phosphonicacid derived from an alkylarnine having from 1 to 20 carbon atoms.

6. A composition of matter comprising a major amount of minerallubricating oil and a minor amount, sufiicient to impart extremepressure to said oil of an ester or" an alkyl amide of trichloromethanephosphonic acid derived from an alkylamine having from 1 to 20 carbonatoms.

7. A composition of matter comprising a major amount of minerallubricating oil and a minor amount, sufiicient to impart extremepressure to said oil, of a C3C18 alkyl amine salt of an alkyl amide oftrichloromethane phosphonic acid derived from an alkylamine having from1 to 20 carbon atoms.

8. A composition of matter comprising a major amount of minerallubricating oil and from about 0.1% to about 10% of N-butylamidotrichloromethane phosphonic acid.

9. A composition of matter comprising a major amount of minerallubricating oil and from about 0.1% to about 10% of di-Z-ethylhexylaminesalt of N-butyl amidotrichloromethane phosphonic acid.

10. A composition of matter comprising a major amount of minerallubricating oil and from about 0.1% to about 10% of N,N-di-n-butyltrichloromethane phosphonic diamide.

11. A composition of matter comprising a major amount of minerallubricating oil and from about 0.1% to about 10% of n-butyl N-butylamido trichloromethanephosphonate.

References Cited in the file of this patent UNITED STATES PATENTS2,573,568 Harman et al. Oct. 30, 1951 2,614,990 Harman et al. Oct. 21,1952 2,683,691 Thorpe July 13, 1954 2,712,029 Van Winkle June 28, 1955

1. A COMPOSITION OF MATTER COMPRISING A MAJOR AMOUNT OF A LUBRICATINGOIL AND A MINOR AMOUNT, SUFFICIENT TO IMPART EXTREME PRESSURE PROPERTIESTO SAID LIQUID OIL, OF A COMPOUND HAVING THE GENERAL FORMULA